中文摘要：

命案现场中最常见的痕迹物证就是血迹.血迹作为诉讼证据具有客观、稳定的特点,通过判断血迹形成时间可以推断案发时间,而死亡时间与案发时间密切相关.死亡时间的推断一直是全世界的法医难题.该文采用光谱分析技术,对玻璃、白色书写纸、塑料膜3种介质上不同陈旧度血迹的吸光度进行分析,探讨其与死亡时间的关系.研究发现,3种介质上的血迹随时间推移,吸光度都呈上升趋势,与死亡时间密切正相关.

英文摘要：

The bloodstain is the most common mark evidence in crime scene.The incident time can be inferred from bloodstain age; also it is closely related to postmortem interval.The estimation of postmortem interval has been the worlds forensic problems.The bloodstain absorption in three different objects of glass,white paper and plastic film has been analyzed to explore the relationship between the postmortem interval and the bloodstain absorption by using the spectroscopy analysis technology in this paper.The study has found that the bloodstain absorption in the three objects presented a rising tendency as time goes on,there exists a positive correlation between bloodstain age and the postmortem interval.